From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Prolonged tests of Le Carbone dynamo brushes, concluding the new combination offers no advantage and is more expensive.
| Identifier | ExFiles\Box 50\5\ Scan391 | |
| Date | 30th November 1925 | |
| X4333 To R.{Sir Henry Royce} from FC. c.c. E.{Mr Elliott - Chief Engineer} CJ. c. By.{R.W. Bailey - Chief Engineer} Wor.{Arthur Wormald - General Works Manager} EFC4/T30.11.25. 20 HP. DYNAMO - LE CARBONE GRADE X MAIN AND EG3399 CONTROL BRUSHES. Prolonged tests have been made of this combination on 20 HP. dynamos. It was a combination recommended by the Le Carbone Co. as likely to be even superior to the Z brushes. Though we have carried out the usual tests, we have not been able to prove any advantage of this Le Carbone combination over the standard Le Carbone Z brushes, so taking into account the fact that brushes in this suggested combination of material would be more expensive, there is no reason for doing anything further. EFC. | ||